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991.
992.
Postoperative management of patients following modified radical mastectomy has changed dramatically in recent years. Historically, patients usually remained in the hospital with closed suction drainage until the amount of drainage had decreased sufficiently for them to be removed. The feasibility of early discharge on the day following surgery was studied in a prospective manner in 29 consecutive breast cancer patients; 27 underwent unilateral modified radical mastectomy and 2 bilateral mastectomies by a single surgeon. All patients were instructed before surgery about planned early discharge and drain care. Twenty-seven of 29 patients (93.3%) were discharged the day following surgery. However, 2 patients refused discharge and were discharged on postoperative Day Two, and one patient was readmitted for confusion. Drains were removed in the office an average of 5.07 days after surgery. Forty-five per cent of patients developed a seroma that required aspiration at least once. No significant long-term sequela were experienced as a result of early discharge. The average hospital cost was reduced by $2,474.00 or 36 per cent (P less than 0.001) as compared to other surgeons in the same medical center who held to traditional postoperative care. The authors conclude that discharge on the day following surgery for patients undergoing a modified radical mastectomy is safe and cost effective.  相似文献   
993.
Altered expression of the genes that control apoptosis and proliferation may influence the response of cancer cells to cytotoxic agents. The primary aim of this study was to determine the role of the novel antiapoptotic and cell cycle gene, survivin, in apoptotsis and proliferation in esophageal cancer and to evaluate whether the survivin, p53, and bcl-2 status were able to predict a patient's response to neoadjuvant therapy. A total of 104 patients with esophageal tumors were studied. Tumor tissue was immunostained for survivin, p53, and bcl-2 proteins. Proliferative and apoptotic activity was measured using ki-67 immunohistochemical analysis and the TUNEL method, respectively. Forty-eight patients whose pretreatment biopsies were analyzed received neoadjuvant chemoradiation therapy or chemotherapy followed by surgery. Outcome was graded as a complete response, a partial response, or no response according to the results of histologic examination and CT imaging. Expression of survivin was found to correlate significantly with the proliferative index but not the apoptotic index. Patients who received neoadjuvant treatment were more likely to achieve a complete response if their tumors had high proliferative activity, and p53 positive tumors were more likely to contain residual tumor after treatment. In conclusion, survivin expression appears to foster proliferative activity in esophageal cancer, and tumors with a high proliferative index or a functioning p53 gene are more responsive to neoadjuvant chemoradiation therapy.  相似文献   
994.
BACKGROUND: Historically, contrast venography has been used to determine renal vein location and assist with vena cava filter placement. This technique, however, exposes the patient to nephrotoxic contrast and radiation. For trauma patients in the intensive care unit (ICU), inferior vena cava filters should ideally be placed without contrast at the bedside to avoid nephrotoxic agents, radiation, and transport of a critically injured patient to the operating room or x-ray department. Previously, the authors have shown that intravascular ultrasound is a safe and accurate method for locating renal veins and assisting with vena cava filter placement. The purpose of this study was to evaluate bedside vena cava filter placement prospectively using only intravascular ultrasound for imaging. METHODS: Between August 2000 and July 2003, 29 patients met trauma service criteria for prophylactic or therapeutic placement of a vena cava filter. The 7 females and 22 males had a mean age of 51.3 years (range, 20-92 years), a mean height of 177 cm (range, 160-218.4 cm), a mean weight of 101.9 kg (range, 59.1-186.4 kg), and a body mass index of 33 (range, 14.7-56.1). Fifteen patients (55.5%) had a body mass index exceeding 30. The mean Injury Severity Score was 25.4 (range, 12-45). Intravascular ultrasound was the sole imaging method, and no contrast or fluoroscopy was used. All procedures were performed in the ICU by trauma surgeons. Data collection was prospective and included demographics, injuries, vena caval anatomy, length of procedure, complications, and follow-up radiographic confirmation of appropriate deployment. RESULTS: The location of the renal veins and vena cava diameter was imaged in all the patients. Three patients were noted to have accessory renal veins, and no patient had thrombus in the vena cava. The inferior vena cava diameter was less than 28 mm in all the patients, thus allowing standard filters to be deployed. Filter deployment was successful for all the patients. Of the 29 patients, 27 had abdominal computed tomography (CT) during their hospital stay. When the location of the renal veins identified by CT was compared with the level of the filter on abdominal x-ray, the filter tip was found to be at or below the level of the most caudal renal vein in 26 of the 27 patients (96.3%). In one patient, the filter tip was purposely placed 2 to 3 cm above an accessory caudal renal vein, but below the main right and left renal veins. The mean procedure time was 37.7 minutes (range, 12-86 minutes). No complications were associated with filter placement. CONCLUSIONS: Intravascular ultrasound is a safe and effective imaging method that may be used for the bedside placement of vena cava filters in the ICU. This technique avoids the use of nephrotoxic intravenous contrast and eliminates the risk of transporting a critically injured patient to the operating room or x-ray department.  相似文献   
995.
996.

Background

In addition to a diagnostic laparoscopy (DL), a routine laparoscopic ultrasound (LUS) has been proposed to identify undetected hepatic metastases and/or anatomically advanced disease in patients with T2 or higher gall bladder cancer (GBC) patients planned for surgical resection. It was hypothesized that a routine LUS is not a cost-effective strategy for these patients.

Methods

Decision tree modeling was undertaken to compare DL-LUS vs. DL at the time of definitive resection of GBC (with no prior cholecystectomy). Costs in US dollars (payer’s perspective), quality-adjusted life weeks (QALWs), and incremental cost-effectiveness ratios (ICER) were calculated (horizon: 6 weeks, willingness-to-pay: $1,000/QALW or $50,000/QALY).

Results

DL-LUS was cost effective at the base case scenario (costs: $30,838 for DL vs. $30,791 for DL-LUS and effectiveness 3.81 QALWs DL vs. 3.82 QALW DL-LUS), resulting in a cost reduction of $9,220 per quality-adjusted life week gained (or $479,469 per QALY). DL-LUS became less cost effective as the cost of ultrasound increased or the probability of exclusion from resection decreased.

Conclusions

Routine LUS with DL for the assessment of resectability and exclusion of metastases is cost effective for patients with GBC. Until improvements in preoperative imaging occur to decrease the probability of exclusion, this appears to be a feasible strategy.  相似文献   
997.

Background

Autoimmune pancreatitis (AIP) is a rare subtype of chronic pancreatitis that may mimic adenocarcinoma of the pancreas. The aim of this study was to evaluate the short-term and long-term outcomes of pancreatectomy for patients with AIP.

Methods

In this multi-institutional study, we identified all patients who underwent pancreatectomy for AIP from 1986 to 2011. AIP was confirmed by pathology review. Clinical presentation, operative details, and postoperative outcomes were analyzed.

Results

Seventy-four patients (median age, 60 years; 69 % male) with AIP underwent pancreatectomy. The main indication for operation was concern for malignancy (n?=?59, 80 %). No patients were found to have pancreatic adenocarcinoma on final pathology. Major complications occurred in ten (14 %) patients, with one perioperative death (1 %). Clinically relevant (grade B/C) pancreatic fistulae occurred in two patients. No patients required reoperation for AIP and 11 (17 %) patients developed recurrent AIP.

Conclusion

Although we do not advocate pancreatectomy for AIP, strong suspicion of malignancy may require an operation in selected patients. For patients with AIP, pancreatectomy resulted in few pancreatic fistulae, a low rate of re-intervention, and a 17 % recurrence rate.  相似文献   
998.
999.
OBJECTIVE: The objective of this study was to determine whether genes that regulate cellular invasion and metastasis are differentially expressed and could serve as diagnostic markers of malignant thyroid nodules. SUMMARY AND BACKGROUND DATA: Patients whose thyroid nodules have indeterminate or suspicious cytologic features on fine needle aspiration (FNA) biopsy require thyroidectomy because of a 20% to 30% risk of thyroid cancer. Cell invasion and metastasis is a hallmark of malignant phenotype; therefore, genes that regulate these processes might be differentially expressed and could serve as diagnostic markers of malignancy. METHODS: Differentially expressed genes (2-fold higher or lower) in malignant versus benign thyroid neoplasms were identified by extracellular matrix and adhesion molecule cDNA array analysis and confirmed by real-time quantitative polymerase chain reaction (PCR). The area under the receiver operating characteristic (AUC) curve was calculated to determine diagnostic accuracy of gene expression level cutoffs established by logistic regression analysis. RESULTS: By cDNA array analysis, ADAMTS8, ECM1, MMP8, PLAU, SELP, and TMPRSS4 were upregulated, and by quantitative PCR, ECM1, SELP, and TMPRSS4 mRNA expression was higher in malignant (n = 57) than in benign (n = 38) thyroid neoplasms (P< 0.002). ECM1 and TMPRSS4 mRNA expression levels were independent predictors of a malignant thyroid neoplasm (P < 0.003). The AUC was 0.956 for ECM1 and 0.926 for TMPRSS4. Combining both markers improved their diagnostic use (AUC 0.985; sensitivity, 91.7%; specificity, 89.8%; positive predictive value, 85.7%; negative predictive value, 82.8%). ECM1 and TMPRSS4 expression analysis improved the diagnostic accuracy of FNA biopsy in 35 of 38 indeterminate or suspicious results. The level of ECM1 mRNA expression was higher in TNM stage I differentiated thyroid cancers than in stage II and III tumors (P < or = 0.031). CONCLUSIONS: ECM1 and TMPRSS4 are excellent diagnostic markers of malignant thyroid nodules and may be used to improve the diagnostic accuracy of FNA biopsy. ECM1 is also a marker of the extent of disease in differentiated thyroid cancers.  相似文献   
1000.
Stokes IA  Clark KC  Farnum CE  Aronsson DD 《BONE》2007,41(2):197-205
Sustained mechanical load is known to modulate endochondral growth in the immature skeleton, but it is not known what causes this mechanical sensitivity. This study aimed to quantify alterations in parameters of growth plate performance associated with mechanically altered growth rate. Vertebral and proximal tibial growth plates of immature rats and cattle, and rabbit (proximal tibia only) were subjected to different magnitudes of sustained loading, which altered growth rates by up to 53%. The numbers of proliferative chondrocytes, their rate of proliferation, and the amount of chondrocytic enlargement occurring in the hypertrophic zone were quantified. It was found that reduced growth rate with compression and increased growth rate with distraction were associated with corresponding changes in the number of proliferative chondrocytes per unit width of growth plate, and in the final (maximum) chondrocytic height in the hypertrophic zone (overall correlation coefficients 0.38 and 0.56 respectively). According to multiple linear regression coefficients for these two variables (0.72 and 1.39 respectively), chondrocytic enlargement made a greater contribution to altered growth rates.  相似文献   
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